Thus far, we have learned that a healthy intestinal barrier is that way because there are a lot of players concertedly making it happen. The community of trillions of microbes living in the gut, the motility of the gastrointestinal tract, a mucous layer, tightly joined cells that make up the intestinal wall, well-functioning immune cells, and so on are the watchmen that perform vital roles in border protection. But when the border patrol is not working as well as it should, things can pass through that otherwise could not.
When the border patrol is working well, it maintains oversight and control over what is and is not allowed to cross the intestinal border. This is called selective permeability, meaning that the border patrol does some inspecting and selecting of what does and does not get to pass through. For example, absorption of key nutrients is allowed, while the absorption of noxious substances is prevented. When this oversight becomes disrupted, increased gut permeability (or leaky gut) occurs, which can potentially promote or aggravate a variety conditions such as obesity, inflammation, and metabolic disease.
A variety of factors can lead to a compromised border, such as chronic stress, environmental toxins, and some medications. Here are a few common substances that we eat or drink that we also need to be aware of:
Emulsifiers are ingredients that are common in processed foods such as many ice creams, icing, many store-bought breads, some margarines, some cakes, some coffee creamers, some infant formulas, and so on. They promote stability, shelf life, and enhance texture and consistency in these foods.
An emulsifier is defined as a substance that stabilizes an emulsion—in particular, a food additive used to stabilize processed foods. Think of a homemade salad dressing that contains oil and water. You mix them together, but they quickly separate unless you add an emulsifier that keeps the oil evenly dispersed in the water.
Just because a substance functions as an emulsifier does not mean it is bad for you. However, there are some that have been found to impair intestinal barrier function. For example, “dietary polysorbate 80 (PS80), a common emulsifier, has been shown to impair intestinal permeability in mice.”[1]
Carboxymethylcellulose is another emulsifier, usually listed under different names on ingredient labels. It was thought to be safe as it passed through the digestive tract, unabsorbed. However, the potential problem with things that are not absorbed is that they come into direct contact with the trillions of bacteria that reside lower in the gut (gut microbiota), and apparently, this is where carboxymethylcellulose can initiate problems by altering the community of gut bacteria.
Alcohol is a leaky gut cocktail. It promotes inflammation in the gut and alters the composition of the community of intestinal microbes and their function. It also increases the permeability of the intestinal lining.[ii] Both the small and large intestine are affected. One mechanism by which alcohol induces gut leakiness is by disrupting the tight junctions between the cells that make up the intestinal lining.[iii] Unfortunately, it also promotes intestinal inflammation, changes the composition and function of the gut microbiota, and affects intestinal immune balance.[iv]
A high-fat diet is another guilty player in creating disturbance at the border. Not all types of fat affect the gut in the same way, but for now, suffice it to say that excess fat in the diet the way we normally do it causes leakiness. It does this in several ways. Researchers found that high fat content in the diet weakens the infantry of certain immune cells that are strategically stationed at the gut, leading to leaky gut.[v] It also stimulates inflammation in the gut and changes the mucous layer and the gut microbiota.[vi]
Managing stress, foregoing soft serve, choosing non-alcoholic options, and learning to enjoy a lower fat diet are all strategies that can keep our watchmen alert and protective.
Scripture points us to the importance of healthy barriers, kept doors, strong gates, protective walls, and of watchmen that keep them. “I have set watchmen on your walls, O Jerusalem; they shall never hold their peace day or night.” Isaiah 62:6. “Set up the standard on the walls of Babylon; make the guard strong, set up the watchmen” Jeremiah 51:12. We need spiritual watchmen in our lives to warn, encourage and protect us.
[1] https://pubmed.ncbi.nlm.nih.gov/33113283/
[ii] https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5513683/
[iii] https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4558329/
[iv] https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5513683/
[v] https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0122195
[vi] https://pubmed.ncbi.nlm.nih.gov/34831387/
